It’s one of the most infamous images in the operatic canon: Salome sealing her obsessive love for Jochanaan with a gruesome kiss upon the lips of his severed head

The opera is Richard Strauss’s Salomé, his adaptation of Oscar Wilde’s fin-de-siècle one-act tragedy of the same name. Salome, step-daughter of King Herod, is overwhelmed by a monomaniacal desire for Jochanaan, the prophet-preacher. When he angrily spurns her advances, she secures his execution by seducing Herod with the proverbial dance of the seven veils (see the video below).

The kiss, which crowns this tragic story, is a disturbingly intimate synthesis of sex, death and religion, the opera’s three central themes.

All through, Struass’s score has an agitated, ominous quality, one moment soaring dramatically, the next shaking with neurotic little phrases that already seem spattered with blood.

“It's a strangely perverse piece,” admits Edwards, “and particularly when you look at the rest of the repertoire of Richard Strauss: a very brave, outrageous piece of composition.”

And bravery must be met with bravery, believes Edwards, although she cautions against getting carried away with too much necrophilic voyeurism.

“To me the kiss is just one component in a larger story, a convoluted sexual power play. Salomé assumes power over Jochanaan by having him killed and over Herod by hoisting him on his own petard,” she says. “He says 'dance for me', and she says 'no'. Then she realises in a flash that this is how she can manipulate the situation. So she gets revenge on both Herod and Jochanaan. Of course, by the end the only power left to Herod is to have her killed.”

Edwards is keen to point to contemporary resonances with the way that the powerless confront fundamentalism and authoritarianism today.

“It's not localised in 2013, but it is eclectic enough to be resonant in today's world, where the powerless only have one alternative: violence.”

In Wilde's play, and in the opera, Jochanaan comes across as a fundamentalist, very Old Testament. According to Edwards, he doesn't have any sort of understanding or ability to reason with Salome. He simply condemns her as the daughter of a slut and a whore.

“And this," says Edwards, "is to a 14-year-old girl!”

At the height of Jochanaan’s rage, when he condemns Salome to hell, there are four pages of instrumentation with no vocal line. What happens on stage in that moment holds the key to the rest of the opera. “She's going through an epiphany which will set up the second half of the story.”

It is as though in that moment, with the weirdly enthralling score, she discovers the dark underside of seduction, last the recourse of the powerless, and one which leads inevitably to violence.

“You talk about the kiss, well that, above all, is the moment when Salomé achieves her desire for power over Jochanaan and finally wreaks her revenge for his denial of her.”